A conventional method of detecting parking spaces for a parking lot is implemented by performing classification, based on various image features, on images of parking spaces that are obtained by sensors observing the parking spaces so as to classify individual parking spaces into an occupied class or a vacant class. To alleviate inter-occlusion problem, shadow problem, lighting problem and perspective problem to which classification of parking spaces in an outdoor parking lot is vulnerable, camera geometry and projection matrix are utilized in the conventional method to select regions of the images of parking spaces appropriate for performance of the classification thereon.
However, it is challenging to utilize a single criteria to perform classification on images of parking spaces with different types of pavement (e.g., grassland, brick floor and asphalt surface). Moreover, non-uniform dimensions of the parking spaces further adversely affect the accuracy of classification of images of parking spaces.